This invention relates to a swivel fitting for a hose, preferably for a gasoline hose. More particularly, the invention relates to a swivel fitting permanently affixed to a hose.
Hose fittings, and in particular, swivel fittings, are known and have been in use for many years. Such fittings are attached to the end of a hose for the further conduit of a liquid or gas. Conventional swivel fittings used on gasoline hoses are reattachable, permitting the removal of the gasoline nozzle or hose and reinstallation and attachment of different swivel nuts and various attachments in the field by any technician or layperson.
Prior art swivel fittings function with a swivel nut secured to a stem piece by means of a retaining ring. The partial assembled fitting, with the retaining ring and swivel nut at the opposing end, is inserted into a hose, over which a ferrule has already been provided. The ferrule is secured to the stem, connecting the hose with the swivel fitting. By design, the conventional retaining ring is removable and the swivel nut can be removed and reinstalled in the field which may lead to safety concerns if the fitting is not reinstalled correctly. In practice, the retaining ring frequently becomes damaged and can come off while in service, resulting in a serious safety problem.
U.S. Pat. No. 4,804,212 discloses a three piece swivel fitting consisting of a nipple to be inserted into the end of a length of hose and secured to the hose by a socket crimped around the end of the nipple and hose. The swivel nut, with internal threading to provide direct metal to metal contact with the nipple for purposes of fluid transfer, is inserted onto the opposing end of the nipple prior to insertion into the hose and crimping. The disclosed fitting is crimped onto the hose assembly in such a manner as to form required wrench flats on the socket, in correspondence to the wrench flats on the swivel nut. The wrench flats on both the socket and swivel nut enable the operator to replace fittings without twisting the hose by providing a means of retaining the opposing ends by wrenches.
The disclosed invention is an externally crimped gasoline hose swivel fitting and a method of providing a crimped-on swivel fitting for a hose. The fitting is a three piece assembly. The first piece is a stem with a shoulder at one external end and a series of hose barbs at the opposing end. A swivel nut is slid over the hose barbs of the stem and retained on the stem by means of the shoulder. The barbed end of the stem is inserted into a hose to which a ferrule with internal notches has already been attached. An internal shoulder on the ferrule rests in a groove on the stem and the ferrule is crimped onto the stem, thereby securing the fitting to the hose.
The swivel nut is retained on the stem by means of the stem shoulder and the crimped ferrule. The swivel nut is provided with external threads permitting attachment of a female fitting gasoline nozzle. The swivel nut on the hose fitting freely rotates 360xc2x0 about the stem, allowing any attached nozzle or further hose attachment to rotate freely around the hose.
The ferrule has a smooth outer circumferential exterior. At one axial end of the ferrule is a radially inwardly extending shoulder, of a dimension to rest in a groove on the stem. Axially inward of the shoulder is a series of internal notches. The internal notching engages the hose and the barbs of the stem to secure the hose during crimping.
Advantages of the invention are cost reductions for the fitting, reduced safety problems associated with known swivel fittings, and improved pullout force of the fitting.